Donovan, F. R. (1964). The vikings. American Heritage Publishing.
Lua i Stíl Chicago (17ú heag.)Donovan, Frank R. The Vikings. New York: American Heritage Publishing, 1964.
Lua MLA (9ú heag.)Donovan, Frank R. The Vikings. American Heritage Publishing, 1964.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.